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How to add column if not exists on PostgreSQL?
...s, _col text, _type regtype)
RETURNS bool AS
$func$
BEGIN
IF EXISTS (SELECT 1 FROM pg_attribute
WHERE attrelid = _tbl
AND attname = _col
AND NOT attisdropped) THEN
RETURN FALSE;
ELSE
EXECUTE format('ALTER TABLE %s ADD COLUMN %I %s...
How do I select elements of an array given condition?
... x = [5, 2, 3, 1, 4, 5] , y = ['f', 'o', 'o', 'b', 'a', 'r'] . I want to select the elements in y corresponding to elements in x that are greater than 1 and less than 5.
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Removing empty lines in Notepad++
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Should first select 'extended` in search mode.
– q0987
Apr 17 '12 at 15:47
14
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The selected run destination is not valid for this action
...ject icon in the left hand panel. 2) In the right hand panel that appears, select Build Settings » all. 3) You'll see the option to change the SDK. Screenshot: img546.imageshack.us/img546/9808/picture3fh.png
– cwd
Dec 16 '11 at 23:12
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Saving results with headers in Sql Server Management Studio
...reopen SSMS after changing this option.
On the SQL Editor Toolbar you can select save to file without having to restart SSMS
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Can I have multiple Xcode versions installed?
... explicitly specify it at install time. Also, you will generally want to unselect all features besides the xcode core tools, because the others don't let you change the install directory.
– Paul Du Bois
Jul 3 '11 at 3:30
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Convert Java Array to Iterable
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+1 I do something similar to create an Iterator<Character> from a String. Implementing your own Iterator seems like the only way to avoid needlessly iterating through all of the values to convert from the object type to the primitive type (via Guava's Ints.asList() for ...
Finding ALL duplicate rows, including “elements with smaller subscripts”
...gt;% filter(n > 1) # data frame
df %>% add_count(col1, col2) %>% select(n) > 1 # logical vector
For duplicate rows (considering all columns):
df %>% group_by_all %>% add_tally %>% ungroup %>% filter(n > 1)
df %>% group_by_all %>% add_tally %>% ungroup %>% ...
Maven: Command to update repository after adding dependency to POM
...:
Right click on the project ->Run As -- >Run configurations.
Then select mavenBuild.
Then click new button to create a configuration of the selected
type .Click on Browse workspace then select your project and in
goals specify eclipse:eclipse
You can refer to how to run the command mvn e...
How to get city name from latitude and longitude coordinates in Google Maps?
... while ((b = stream.read()) != -1) {
stringBuilder.append((char) b);
}
} catch (ClientProtocolException e) {
} catch (IOException e) {
}
JSONObject jsonObject = new JSONObject();
try {
jsonObject = new JSONObject(stringBuilder.toString());
} c...